In the related art, various devices are proposed, which estimate a self position of a moving body based on sensor values from internal sensors such as an encoder or a gyroscope and a camera mounted on the moving body such as a robot or a vehicle.
For example, in Patent Literature 1 (JP-A-2005-315746) described below, a self position identification method of an autonomously travelling moving body under an environment in which multiple landmarks are arranged on the upper part of a room is characterized by including: a step of measuring the multiple landmark positions in advance and pre-registering the coordinates on an absolute coordinate system with a reference; a step of extracting a landmark candidate point from an image captured upward direction by a wide angle camera mounted on the moving body and calculating a two-dimensional candidate point coordinate corresponding to the extracted candidate point, a step of setting multiple arbitrary virtual points in a travelling region of the moving body on the absolute coordinate system and respectively deriving the two-dimensional coordinates of the landmarks on the image that can be obtained in a case where the moving body is present on the virtual point using the three-dimensional registration position coordinates, and a step of respectively comparing the coordinates of the candidate point and the two-dimensional coordinates and estimating the virtual point of the moving body corresponding to the two-dimensional coordinates most approximate to the candidate point coordinates as the self position of the moving body.
According to the Literature, the multiple virtual points are set, and then, the self position is estimated from the two-dimensional coordinates of the landmark in the virtual points and the candidate point coordinates of the landmark extracted from the image captured by the wide angle camera. Therefore, without a need for identification of the individual landmark, and further, even in a case where only a part of the landmark can be extracted from the image captured by the wide angle camera due to an unclear viewing range, it is possible to stably and accurately estimate the self position of the moving body. Furthermore, self position identification robust to the environment disturbance such as a change of lighting can be achieved, and in addition, the self position identification strong to the external disturbance due to a shielding obstacle or the like can be performed because the upward image such as a ceiling is used. Moreover, since the wide angle camera such as a camera using a fish-eye lens or an omnidirectional camera is used, a field of view becomes wide, and thus, the self position identification can be performed without needing the multiple landmarks.